Air diffuser, and mold and method for its production

• US 5,938,525 A
• Filed: 07/23/1997
• Issued: 08/17/1999
• Est. Priority Date: 07/23/1997
• Status: Expired due to Term

• Current Assignee: Air Distribution Technologies IP, LLC
• Original Assignee: Tomkins Industries Incorporated
• Inventors: Porter, Kennon B., Birdsong, John R.
• Primary Examiner(s): Joyce, Harold
• Application Number:
  US08/899,345
• Time in Patent Office: 755 Days
• Field of Search: 454/289, 454/290, 454/324, 454/334
• US Class Current: 454/290
• CPC Class Codes: B64D 2013/003 Cabin ventilation nozzles
• CPC Class Codes: F24F 13/065 formed as cylindrical or spherical bodies which are rotatable

Abstract

An air diffuser for under floor air and electrical distribution systems, which can be rapidly converted to a cable grommet assembly, is provided with a diffuser grille having generally helical slots that produce a swirling air flow pattern with low impulse, low turbulence and high induction. The helical air slots allow the grille to be rotated or spun off a mold, which allows the grilles to be molded more rapidly and economically. The grille sets on a housing which contains a flow regulator. Both the housing and the flow regulator have side walls with air slots. The regulator is connected to the grille and can be rotated by rotating the grille to regulate that air flow through the diffuser. The air diffusers and cable grommet assemblies are supported by common mounting systems that can be installed through the floors of overlying an air distribution and electrical cable plenum. The mounting system includes a trim ring installed in a hole in the floor, which supports the other components of the air diffuser or grommet assembly, and a retaining ring which is dropped through the hole before the trim ring is installed and then ratcheted onto the trim ring.

Claims

1. An air diffuser for an air distribution system having a plenum that is separated by a panel from a space to be heated, cooled or ventilated, comprising:

a mount for supporting said diffuser in an opening in said panel;

a housing with one or more openings that permit air to enter said diffuser from said plenum; and

a grille having a plurality of curved, helical air slots through which air is discharged from the diffuser into said space, said slots having sloping sides that are substantially straight from the top of arcuate cross-sections through said slots to the bottom of said arcuate cross-sections, wherein the slope of the sides of said arcuate cross-sections varies as a function of radial distances from a center of said grille to said arcuate cross-sections.

2. An air diffuser in accordance with claim 1 wherein said helical slots extend generally outward from a central hub of said grille and the slope of said slots increases as the distance from said hub increases.

3. An air diffuser in accordance with claim 2 wherein the ratio of the lateral offset from top to bottom of any slot at any first location along said slot to the lateral offset at any second location along the slot is substantially equal to the ratio of the radial distance from the center of said grille to the radial distance to said second location.

4. An air diffuser according to claim 2 wherein the ratio of the width of the base of a right triangle formed by an arcuate section through one of said slots, wherein the side of said slot defines the hypotenuse of said triangle, to the width of the base of a second right triangle formed by another arcuate section through one of said slots at a different distance from the center of said grille is substantially equal to the ratio of the distance from the center of grille to said first right triangle to the distance to said second right triangle.

5. An underfloor air diffuser comprising:

a housing having a top ring surface thereon defining an air opening therein and a side wall surface having air slots therethrough; and

a diffuser grille having a plurality of curved, helically oriented air slots extending through said grille from top to bottom, said slots having sloping sides that are substantially straight from the top of arcuate cross-sections through said grille to the bottom of said cross-sections, said sides having a slope that varies as a function of radial distance from a center of said grille, said grille also having a bottom ring surface engaging said top ring surface of said housing.

6. The underfloor diffuser apparatus of claim 5 wherein said helically oriented air slots of said diffuser grille have a geometry wherein the proportion of the width of a base of a right triangle formed by a first arcuate section extending through a first point of a slot and the width of a base of a right triangle formed by a second arcuate section extending through a second point of a slot is substantially equal to the proportion of the distance from a center point of the grille to the first arcuate section and a distance from the center point of the grille to the second arcuate section.

7. An underfloor air diffuser apparatus comprising a diffuser grille having a plurality of air slots therethrough wherein said plurality of air slots are configured with a geometry wherein the proportion of the width of a base of a right triangle formed by a first arcuate section extending through a first point of a slot and the width of a base of a right triangle formed by a second arcuate section extending through a second point of a slot is substantially equal to the proportion of the distance from a center point of the grille to the first arcuate section and a distance from the center point of the grille to the second arcuate section.